package com.cityu.bac.rfidDriver;

import java.io.File;
import java.io.FileDescriptor;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;

import android.util.Log;

class SerialPort {

	private static final String TAG = "SerialPort";

	/*
	 * Do not remove or rename the field mFd: it is used by native method close();
	 */
	protected FileDescriptor mFd;
	protected InputStream mInputStream;
	protected OutputStream mOutputStream;

	public SerialPort(){
	    
	}
	
	public String getName(){
		return "usb-serial";
	}
	
	SerialPort(File device, int baudrate) throws SecurityException, IOException {

		/* Check access permission */
//		if (!device.canRead() || !device.canWrite()) {
//			try {
//				/* Missing read/write permission, trying to chmod the file */
//				Process su;
//				su = Runtime.getRuntime().exec("/system/bin/su");
//				String cmd = "chmod 666 " + device.getAbsolutePath() + "\n"
//						+ "exit\n";
//				su.getOutputStream().write(cmd.getBytes());
//				if ((su.waitFor() != 0) || !device.canRead()
//						|| !device.canWrite()) {
//					throw new SecurityException();
//				}
//			} catch (Exception e) {
//				e.printStackTrace();
//				throw new SecurityException();
//			}
//		}

		mFd = open(device.getAbsolutePath(), baudrate);
		if (mFd == null) {
			Log.e(TAG, "native open returns null");
			throw new IOException();
		}
		mInputStream = new FileInputStream(mFd);
		mOutputStream = new FileOutputStream(mFd);
	}

	// Getters and setters
	InputStream getInputStream() {
		return mInputStream;
	}

	OutputStream getOutputStream() {
		return mOutputStream;
	}

	// JNI
	private native static FileDescriptor open(String path, int baudrate);
	native void close();
	static {
		try{
			System.loadLibrary("serial_port");
		}catch(UnsatisfiedLinkError ule){
			Log.e("JNI", "WARNING: Could not load libserial_port.so :" + ule.toString());
		}
	}
}
